local api = vim.api
local HOME = os.getenv('HOME')
local M = {}
local log_level = 'INFO'


function M.visualize(opts)
  opts = opts or {}
  local varname = opts.varname or vim.fn.expand("<cexpr>")
  local child_names = (
    opts.child_names
    or vim.split(vim.fn.input({ prompt = "Child Properties: " }), " ")
  )
  local property_names = (
    opts.property_names
    or vim.split(vim.fn.input({ prompt = "Properties: " }), " ")
  )
  local session = require("dap").session() or {}
  local scopes = (session.current_frame or {}).scopes
  local variable = nil
  for _, scope in pairs(scopes or {}) do
    variable = scope.variables[varname]
    if variable then
      break
    end
  end
  if not variable then
    return
  end
  variable = variable --[[@as dap.Variable]]
  local f = assert(io.open("/tmp/dap.gv", "w"), "Must be able to open file")
  coroutine.wrap(function()
    f:write("digraph G {\n")
    f:write("  graph [\n")
    f:write("     layout=dot\n")
    f:write("     labelloc=t\n")
    f:write("  ]\n")

    ---@param v dap.Variable
    ---@return dap.Variable[]
    local function get_children(v)
      if v.variablesReference == 0 then
        return {}
      end
      local params = {
        variablesReference = v.variablesReference
      }
      local err, result = session:request("variables", params)
      assert(not err, err and require("dap.utils").fmt_error(err))
      return result.variables
    end

    ---@param v dap.Variable
    ---@return dap.Variable
    local function resolve_lazy(v)
      if (v.presentationHint or {}).lazy then
        local resolved = get_children(v)[1]
        resolved.name = v.name
        return resolved
      end
      return v
    end

    ---@param parent dap.Variable
    local function add_children(parent, parent_name)
      local children = get_children(parent)
      parent_name = parent_name or parent.name
      local property_values = {}
      for _, var in pairs(children) do
        if vim.tbl_contains(property_names, var.name) then
          if var.variablesReference > 0 then
            for _, child_var in pairs(get_children(var)) do
              table.insert(property_values, var.name .. ": " .. resolve_lazy(child_var).value)
            end
          else
            table.insert(property_values, var.value)
          end
        end
      end
      for _, var in pairs(children) do
        local name = parent_name .. "." .. var.name
        var = resolve_lazy(var)
        if vim.tbl_contains(child_names, var.name) or tonumber(var.name) then
          if var.value ~= "" then
            f:write(string.format(
              '  "%s" [label=<<b>%s</b><br/>%s>]\n',
              name,
              name,
              table.concat(property_values, "<br/>")))
          else
            f:write(string.format('  "%s"\n', name))
          end
          f:write(string.format('  "%s" -> "%s"\n', parent_name, name))
          add_children(var, name)
        end
      end
    end

    variable = resolve_lazy(variable)
    f:write(string.format('  "%s"\n', variable.name))
    add_children(variable)
    f:write("}")
    f:close()
    vim.fn.system("dot -Txlib /tmp/dap.gv")
  end)()
end


local function add_tagfunc(widget)
  local orig_new_buf = widget.new_buf
  widget.new_buf = function(...)
    local bufnr = orig_new_buf(...)
    api.nvim_buf_set_option(bufnr, "tagfunc", "v:lua.require'me.lsp'.symbol_tagfunc")
    return bufnr
  end
end


local function reload()
  local m = require('me')
  require('dap.repl').close()
  m.reload('dap', true)
  m.reload('me.dap').setup()
  m.reload('jdtls.dap').setup_dap({hotcodereplace = 'auto'})
  vim.cmd('set ft=' .. vim.bo.filetype)
  require('dap').set_log_level(log_level)
end


function M.setup()
  local dap = require('dap')

  api.nvim_create_autocmd("WinEnter", {
    callback = function()
      local win = api.nvim_get_current_win()
      local value = (
        (vim.bo.buftype == "" and package.loaded.dap and require("dap").session())
        and "yes:1"
        or "auto"
      )
      vim.wo[win].signcolumn = value
    end,
  })
  api.nvim_create_autocmd("User", {
    group = api.nvim_create_augroup("dap", { clear = true }),
    pattern = "DapProgressUpdate",
    command = "redrawstatus"
  })

  local orig_set_log_level = dap.set_log_level
  ---@diagnostic disable-next-line: duplicate-set-field
  function dap.set_log_level(level)
    orig_set_log_level(level)
    log_level = level
  end

  local widgets = require('dap.ui.widgets')
  add_tagfunc(widgets.expression)
  add_tagfunc(widgets.scopes)
  local keymap = vim.keymap
  local function set(mode, lhs, rhs)
    keymap.set(mode, lhs, rhs, { silent = true })
  end
  set({'n', 't'}, '<F3>',  dap.terminate)
  set({'n', 't'}, '<F5>',  dap.continue)
  set('n', '<leader>b', dap.toggle_breakpoint)
  set('n', '<leader>B', function()
    local line = vim.trim(api.nvim_get_current_line())
    local default
    if vim.bo.filetype == "java" then
      local assert_condition = line:match("^assert ([^:]*)")
      if assert_condition then
        default = vim.trim("!" .. assert_condition)
      end
    end
    local condition = vim.fn.input({ prompt = 'Breakpoint Condition: ', default = default})
    if condition and condition ~= "" then
      dap.toggle_breakpoint(condition, nil, nil, true)
    end
  end)
  set('n', '<leader>lp', function()
    local logpoint = vim.fn.input({ prompt = 'Log point message: '})
    if logpoint then
      dap.toggle_breakpoint(nil, nil, logpoint, true)
    end
  end)
  set('n', '<leader>lv', function()
    local variable = vim.fn.expand("<cexpr>")
    local logpoint = string.format("%s={%s}", variable, variable)
    if logpoint then
      dap.toggle_breakpoint(nil, nil, logpoint, true)
    end
  end)
  set('n', '<leader>dr', function() dap.repl.toggle({height=15}) end)
  set('n', '<leader>dR', dap.restart_frame)
  set('n', '<leader>dl', function()
    if vim.bo.modified and vim.bo.buftype == '' then
      vim.cmd.w()
    end
    dap.run_last()
  end)
  set('n', '<leader>dj', dap.down)
  set('n', '<leader>dk', dap.up)
  set('n', '<leader>dc', dap.run_to_cursor)
  set('n', '<leader>dg', dap.goto_)
  set('n', '<leader>dS', function() widgets.centered_float(widgets.frames) end)
  set('n', '<leader>dt', function() widgets.centered_float(widgets.threads) end)
  set('n', '<leader>ds', function() widgets.centered_float(widgets.scopes) end)
  set({'n', 'v'}, '<leader>dh', widgets.hover)
  set({'n', 'v'}, '<leader>dp', widgets.preview)
  set("n", "<leader>di", function()
    dap.repl.open()
    dap.repl.execute(vim.fn.expand("<cexpr>"))
  end)
  set("x", "<leader>di", function()
    local lines = vim.fn.getregion(vim.fn.getpos("."), vim.fn.getpos("v"))
    dap.repl.open()
    dap.repl.execute(table.concat(lines, "\n"))
  end)

  dap.listeners.after.event_initialized['me.dap'] = function()
    set("n", "<up>", dap.restart_frame)
    set("n", "<down>", dap.step_over)
    set("n", "<left>", dap.step_out)
    set("n", "<right>", dap.step_into)
    for _, win in ipairs(api.nvim_list_wins()) do
      if vim.bo[api.nvim_win_get_buf(win)].buftype == "" then
        vim.wo[win].signcolumn = "yes:1"
      end
    end
  end
  local after_session = function()
    if not next(dap.sessions()) then
      pcall(keymap.del, "n", "<up>")
      pcall(keymap.del, "n", "<down>")
      pcall(keymap.del, "n", "<left>")
      pcall(keymap.del, "n", "<right>")
      for _, win in ipairs(api.nvim_list_wins()) do
        vim.wo[win].signcolumn = "auto"
      end
    end
  end
  dap.listeners.after.event_terminated['me.dap'] = after_session
  dap.listeners.after.disconnect['me.dap'] = after_session

  local sidebar = widgets.sidebar(widgets.scopes)
  local create_command = api.nvim_create_user_command
  create_command('DapSidebar', sidebar.toggle, { nargs = 0 })
  create_command('DapReload', reload, { nargs = 0 })
  create_command('DapBreakpoints', function() dap.list_breakpoints(true) end, { nargs = 0 })
  create_command('DapVisualize', function() M.visualize() end, { nargs = 0 })
  create_command("DapNew", function() dap.continue({ new = true }) end, { nargs = 0 })

  create_command("DapDiff", function(cmd_args)
    local fargs = cmd_args.fargs
    local max_level = nil
    if #fargs == 3 then
      max_level = tonumber(fargs[3])
    elseif #fargs ~= 2 then
      error("Two or three arguments required")
    end
    require("dap.ui.widgets").diff_var(fargs[1], fargs[2], max_level)
  end, { nargs = "+" })

  local sessions_bar = widgets.sidebar(widgets.sessions, {}, '5 sp')
  create_command("DapSessions", sessions_bar.toggle, { nargs = 0 })


  dap.defaults.fallback.switchbuf = 'usetab,uselast'
  dap.defaults.fallback.terminal_win_cmd = 'tabnew'
  dap.defaults.python.terminal_win_cmd = 'belowright new'
  dap.defaults.fallback.external_terminal = {
    command = '/usr/bin/alacritty';
    args = {'--hold', '-e'};
  }
  dap.adapters.cppdbg = {
    id = 'cppdbg',
    type = 'executable',
    command = HOME .. '/apps/cpptools/extension/debugAdapters/bin/OpenDebugAD7',
  }
  dap.adapters.gdb = {
    type = "executable",
    command = "gdb",
    args = { "-i", "dap" }
  }
  dap.adapters["gdb-arm"] = {
    type = "executable",
    command = "arm-none-eabi-gdb",
    args = { "-i", "dap" }
  }
  dap.adapters.codelldb = {
    type = 'server',
    port = "${port}",
    executable = {
      command = HOME .. '/apps/codelldb/extension/adapter/codelldb',
      args = {"--port", "${port}"},
    }
  }
  dap.adapters.lldb = {
    type = 'executable',
    command = '/usr/bin/lldb-vscode',
    name = "lldb"
  }

  local function program()
    local path = vim.fn.input({
      prompt = 'Path to executable: ',
      default = vim.fn.getcwd() .. '/',
      completion = 'file'
    })
    return (path and path ~= "") and path or dap.ABORT
  end

  -- Dont forget, attach needs permission:
  --  echo 0 | sudo tee /proc/sys/kernel/yama/ptrace_scope
  local configs = {
    {
      name = "gdb: Launch",
      type = "gdb",
      request = "launch",
      program = require("dap.utils").pick_file,
      cwd = '${workspaceFolder}',
    },
    {
      name = "gdb-arm: Attach target",
      type = "gdb-arm",
      request = "attach",
      program = program,
      target = "localhost:3333",
      cwd = '${workspaceFolder}',
    },
    {
      name = "gdbserver: attach",
      type = "gdb",
      request = "attach",
      target = "localhost:1234",
      cwd = '${workspaceFolder}',
    },
    {
      name = "cppdbg: Launch",
      type = "cppdbg",
      request = "launch",
      program = program,
      cwd = '${workspaceFolder}',
      externalConsole = false,
      args = {},
    },
    {
      name = "cppdbg: Attach",
      type = "cppdbg",
      request = "Attach",
      processId = function()
        return tonumber(vim.fn.input({ prompt = "Pid: "}))
      end,
      program = program,
      cwd = '${workspaceFolder}',
      args = {},
    },
    {
      name = "codelldb: Launch",
      type = "codelldb",
      request = "launch",
      program = program,
      cwd = '${workspaceFolder}',
      args = {},
    },
    {
      name = "codelldb: Launch external",
      type = "codelldb",
      request = "launch",
      program = program,
      cwd = '${workspaceFolder}',
      args = {},
      terminal = 'external',
    },
    {
      name = "codelldb: Attach (select process)",
      type = 'codelldb',
      request = 'attach',
      pid = require('dap.utils').pick_process,
      args = {},
    },
    {
      name = "codelldb: Attach (input pid)",
      type = 'codelldb',
      request = 'attach',
      pid = function()
        return tonumber(vim.fn. input({ prompt = 'pid: '}))
      end,
      args = {},
    },
    {
      name = "lldb: Launch (integratedTerminal)",
      type = "lldb",
      request = "launch",
      program = program,
      cwd = '${workspaceFolder}',
      stopOnEntry = false,
      args = {},
      runInTerminal = true,
    },
    {
      name = "lldb: Launch (console)",
      type = "lldb",
      request = "launch",
      program = program,
      cwd = '${workspaceFolder}',
      stopOnEntry = false,
      args = {},
      runInTerminal = false,
    },
    {
      name = "lldb: Attach to process",
      type = 'lldb',
      request = 'attach',
      pid = require('dap.utils').pick_process,
      args = {},
    },
    setmetatable(
      {
        name = "Neovim",
        type = "cppdbg",
        request = "launch",
        program = os.getenv("HOME") .. "/dev/neovim/neovim/build/bin/nvim",
        cwd = os.getenv("HOME") .. "/dev/neovim/neovim/",
        externalConsole = true,
        args = {
           "--clean",
           "--cmd",
           "call getchar()",
        }
      },
      {
        __call = function(config)
          local key = "me.neovim"
          dap.listeners.after.initialize[key] = function(session)
            session.on_close[key] = function()
              for _, handler in pairs(dap.listeners.after) do
                handler['me.neovim'] = nil
              end
            end
          end
          dap.listeners.after.event_process[key] = function(_, body)
            dap.listeners.after.initialize[key] = nil
            local ppid = body.systemProcessId
            vim.wait(1000, function()
              return tonumber(vim.fn.system("ps -o pid= --ppid " .. tostring(ppid))) ~= nil
            end)
            local pid = tonumber(vim.fn.system("ps -o pid= --ppid " .. tostring(ppid)))
            if pid then
              dap.run({
                name = "Neovim embedded",
                type = "cppdbg",
                request = "attach",
                program = os.getenv("HOME") .. "/dev/neovim/neovim/build/bin/nvim",
                processId = pid,
                cwd = os.getenv("HOME") .. "/dev/neovim/neovim/",
                externalConsole = false,
              })
            end
          end
          return config
        end
      }
    ),
  }
  dap.configurations.c = configs
  dap.configurations.rust = configs
  dap.configurations.cpp = configs
  dap.configurations.zig = {
    {
      name = "Zig run",
      type = "gdb",
      request = "launch",
      program = "/usr/bin/zig",
      args = {"run", "${file}"},
      cwd = "${workspaceFolder}",
    },
    {
      name = "Program",
      type = "gdb",
      request = "launch",
      program = program,
      args = {},
      cwd = "${workspaceFolder}",
    },
    {
      name = "Test (No breakpoints 😢)",
      type = "gdb",
      request = "launch",
      program = "/usr/bin/zig",
      args = {"test", "-fno-strip", "${file}"},
      cwd = "${workspaceFolder}",
      setupCommands = {
        {
          text = "set follow-fork-mode child",
        },
        {
          text = "set detach-on-fork off",
        },
      }
    },
  }
end


return M
